The point on the unit circle with centre (0, 0); where tangents are equally inclined to the co-ordinate axes are : |
$(\frac{1}{\sqrt{2}},-\frac{1}{\sqrt{2}}),(-\frac{1}{\sqrt{2}},\frac{1}{\sqrt{2}})$ $±1, ±1), (±1, ±1)$ $(±\sqrt{2},±\sqrt{2}), (±\sqrt{2}, ±\sqrt{2})$ $(±2\sqrt{2},±2\sqrt{2}), (±2\sqrt{2}, ±2\sqrt{2})$ |
$(\frac{1}{\sqrt{2}},-\frac{1}{\sqrt{2}}),(-\frac{1}{\sqrt{2}},\frac{1}{\sqrt{2}})$ |
The correct answer is Option (1) → $(\frac{1}{\sqrt{2}},-\frac{1}{\sqrt{2}}),(-\frac{1}{\sqrt{2}},\frac{1}{\sqrt{2}})$ unit circle with centre (0, 0) $⇒x^2+y^2=1$ ...(1) so $2x+2y\frac{dy}{dx}=0⇒\frac{dy}{dx}=-\frac{x}{y}$ point of equal inclination $⇒\frac{dy}{dx}=1$ $⇒-x=y$ so from (1) $x^2+x^2=1$ $x=±\frac{1}{\sqrt{2}}$ $y=\mp\frac{1}{\sqrt{2}}$ so points → $(\frac{1}{\sqrt{2}},-\frac{1}{\sqrt{2}}),(-\frac{1}{\sqrt{2}},\frac{1}{\sqrt{2}})$ |